Yahoo Audio Search streams 30 second preview clips of songs in their audio search with links to download (read: buy) the song where available. The preview is a smart and natural addition to any audio search, but it's the first we've seen from a popular search box. Beyond that, clicking the download locations link provides a great table detailing not only where you can buy the song, but also the price, format, supported platform and whether the song can be burned to CD or copied. Previously mentioned Yahoo lyrics was already a great leap in song search, and it looks like they're continuing to establish themselves as the only worthwhile audio/music search currently available.